Semi-empirically derived petrophysical and thermodynamical coefficients of permselective shales—Implications on ore mineralization |
| |
Authors: | Peter G Oduor X Santos K Forward N Sharp C Bue F Casey J Abwawo |
| |
Institution: | aDepartment of Geosciences, North Dakota State University, Fargo, ND 58105, USA;bDepartment of Forestry, Mississippi State University, MS 39762, USA;cDepartment of Civil Engineering, North Dakota State University, Fargo, ND 58105, USA;dDepartment of Soil Sciences, North Dakota State University, Fargo, ND 58105, USA;eDepartment of Mathematics, Tacoma Community College, WA 98466, USA |
| |
Abstract: | Phenomenological coefficients of shale–electrolyte systems may offer a glimpse into probable matrix-permeability and solute-exclusionary relationships. Shales from unexposed Upper Cretaceous Period Mancos Shale and from Permian Period Abo Formation were cut into thin wafers, placed in custom built osmometers and a chemical potential applied across them giving rise to induced osmotic flow. This in turn spawned matrix unique constants namely mechanical filtration coefficient LP (m3 N−1 s−1), diffusional mobility per unit osmotic pressure LPD (m3 N−1 s−1), osmotic flow coefficient; LD (m3 N−1 s−1), reflection coefficient σ (dimensionless) at zero gradients of temperature and hydrostatic pressure. Considering intrinsic relationships between these constants where and LPD = −σLP, we have ascertained that the bentonitic fossiliferous Mancos shale had a lower LP and a higher σ compared to the kaolinitic and siliceous shale from Abo Formation indicating a higher degree of compaction post-diagenesis (lower porosity) and higher filtration efficiency. Mechanistic processes involved in solute transport and matrix morphology indicate key multi-scale transformations, ionic- and atomic-exchange competitions on high energy sites like cation-exchange sites, isomorphic substitution at argillaceous mineral edges, atomic-clipping within basal spacing, preferential pathway migration, dead-end pores that give rise to localized solute exclusionary processes and solute attenuation giving rise to anomalous osmotic gradients. |
| |
Keywords: | Osmosis Phenomenological coefficients Irreversible thermodynamics |
本文献已被 ScienceDirect 等数据库收录! |
|